1. Field of the Invention
This invention relates generally to laser initiation of explosives and other pyrotechnic devices and more particularly to laser diodes for initiating explosive devices that have built-in self check capabilities to check the continuity of the optical circuit and also to provide a safe and arm condition with a device preventing inadvertent ignition of the explosive by the laser. Problems, such as, electrostatic discharges, stray currents, and electrical interference associated with the use of electronic detonators are well documented. As a result, designers have been inclined more and more to utilize laser initiating devices because they have proven to be safer from the hazards associated with electronic detonating devices.
However, even with laser initiating devices, such as the one proposed herein, it would still be desirable if there was a means of checking the continuity of the optical circuit from the laser power source to the explosives. Also, it would be desirable to have a safe and arm feature wherein the laser power source is locked out from initiating a firing sequence prematurely.